You're The Only Damn Exception
by Dreaming-Of-A-Nightmare
Summary: "I never make exceptions. An exception disproves the rule." Because that's common, scientific sense, isn't it? And as part of the rule of thumb, one should never become emotionally invested where cases are involved. .:. one-sided Johnlock. twoshot.
1. John is The Exception

**A/N: Now that I am reading the Sherlock Holmes books (all of them; I bought two volumes that, together, make up the entire collection of all of Sir Arthur Conan Doyle's Sherlock Holmes works), I am seeing all the slash and finding all sorts of inspirations for fanfiction, as well as all the little details and phrases (albeit modernized) that are slipped into the BBC's series, as well as all the cases adapted well for it. It's all amazing, really.**

**And as you will tell by the following quote, here is where some of that inspiration comes in. ;D**

**This is post-Reichenbach drabble, but that will be explained. And yes, I do fancy using Mary, even though we haven't met her yet. And somehow, that's the beauty of it, isn't it?**

**EDIT: Now improved thanks to my lovely dear incessantbeat on Tumblr! :D **

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><p>Mary Morstan just left 221b and Watson watched her go. After she was out of sight, this is what transpired:<p>

"_What a very attractive woman!" I exclaimed, turning to my companion._

_He had his pipe again and was leaning back with drooping eyelids. "Is she?" he said languidly. "I did not observe."_

"_You really are an automaton – a calculating machine," I cried. "There is something positively inhuman in you at times."_

_He smiled gently._

"_It is of the first importance," he cried, "not to allow your judgment to be biased by personal qualities. A client to me is a mere unit, a factor in a problem. The emotional qualities are antagonistic to clear reasoning. I assure you that the most winning woman I ever knew was hanged for poisoning three little children for their inheritance-money, and the most repellent man of my acquaintance is a philanthropist who has spent nearly a quarter of a million upon the London poor."_

_"In this case, however –"_

"_I never make exceptions. An exception disproves the rule."_

The Sign of Four (final page of chapter 2); Sir Arthur Conan Doyle.

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><p>Rule of Thumb: Never get emotionally attached, particularly to a case or its client(s), and <em>never <em>make exceptions.

John seems to think this rule of thumb is rubbish, because here he is, not six months following Sherlock's return from the grave, and he's becoming emotionally invested in their new client, a young woman by the name of Mary Morstan.

She just left their flat after explaining their problem. And, being as bored as he is, Sherlock decided to give it a go. A missing father is interesting, although he is pretty sure he has it worked out that the man is dead. He's been gone for years, after all. But as to the _how _concerning his disappearance and death is precisely what Sherlock is interested in.

"God, she was attractive, wasn't she?" John remarks after he glances out the window, watching her leave Baker Street.

"Was she?" Sherlock says idly as he moves for his nicotine patches; only a single-patch problem, nothing serious. Some investigation necessary in a moment, after he's worked out a plan. "I hadn't noticed."

"Hadn't – hadn't _noticed? _Are you blind, Sherlock? I mean, I know dating and whatnot isn't _your area, _but can you honestly sit there and tell me that you didn't at all see how beautiful she was?" John says, clearly baffled. "You know, sometimes I wonder about you, I really do. You're like a machine."

"And this is news to you?" Sherlock replies with a slight smirk. "I've told you many times that my brain is my harddrive, and I can delete or add information to it at will. That's the defintion of a computer, John, and – shocker! – computers are machines."

"Yes, but – even in this case, can't you –"

"I never make exceptions. Clients are units of data, like file folders, and their cases go inside them; nothing more," Sherlock answers swiftly and casually. He leans back in his chair, patch in place on her forearm, and closes his eyes as he touches his fingertips together and raises his index fingers to lightly press against his lips. "Exceptions disprove the rules in science, and they also do so in life. It's common sense, John."

"…_Honestly_," John scoffs, turning away again, unsure for a moment of what to do with himself before deciding to make tea.

But as he walks away, Sherlock peeks one eyes open, just halfway, and sighs out through his nose when he closes it again, because he is being a hypocrite.

When he had opened his eye, he watched John walk into the kitchen, watched his every move. So when he closed it again, he sighed disappointedly at himself, because John will forever be an exception to every rule Sherlock has laid out for himself.

Sherlock doesn't have friends. Never has, and never thought he would. Allies, yes, but friends? Never. Allies are useful; they are people he can use as aid in whatever field necessary; as examples, Molly Hooper in the medical field, and Greg Lestrade in the police force. Two people who can gain him access to what he needs for his cases. And they are two people he would call, surely, if he needed a favor for things like his cases. But friends? He would never deem them to be 'friends,' even if they've had Christmas get-togethers at his flat, and even if Moriarty threatened their lives (because Molly was, Sherlock discovered, on the list of "everyone").

However, Dr. John Watson is his friend. A true friend, someone who can be safely deemed so, because he would go to John not just for cases or about his cases, but for anything. He would ask John for anything, because he trusts John completely. And unlike having Molly or Lestrade wounded or killed, Sherlock would seek revenge for John. And he did; because of John's sake, for his protection, namely, and not solely for the protection of others (because John came first to mind; he thought John would be Moriarty's only target, until Moriarty elaborated), Sherlock went after every last assassin until he found John's, a sniper named Sebastian Moran, whom Sherlock discovered was Moriarty's own right-hand man, like John is Sherlock's.

And then there are other exceptions John fulfills, ones Sherlock doesn't bare thinking about often, but when he does, he quickly denies it and moves on, because that is what he does best.

As John returns to the living room with tea, Sherlock accepts a cup – two sugars, like he likes his coffee – and raises it to his lips. He doesn't open his eyes. He keeps right on thinking about exceptions and how John is one, and how he can understand why Mary is John's. He is only thinking of these things distantly, of course; the rest of his mind is focused entirely on the nature of this missing person's case and how it can be puzzled out.

Sighing again as he peeks open one eye and sets down his teacup (glancing briefly in John's direction, where his flatmate is holding up a newspaper and reading it), Sherlock can't help but feel like a fool. To say that John is his _only _exception, the lone one that defies the rules, it still enough to irk him. Even if there is but one exception in a sea of possibilities to exceptions (Irene Adler another whole person who comes to mind as part of that sea), it doesn't excuse the fact that there _is _an exception.

Sherlock wonders, sometimes, if he is truly a sociopath, or if the label was slapped on prematurely or incorrectly, by himself and Mycroft's nosy therapists over the early years of Sherlock's life. Because don't sociopaths also not have exceptions? Don't they refuse to ever compromise? Aren't they incapable or very poor at secreting certain chemicals in the brain associated with social recognition with things like friends and the like?

And yet here Sherlock is with an _exception, _a _compromise, _an _anomaly, _an _incriminating factor. _Because he is guilty; this does constitute as evidence, like a crime, of Sherlock's own betrayal to his precious rules. Fucking John Watson, an army doctor, a humble man, a generous soul, a strong heart, a brave companion; he somehow has all of the qualities of someone who is just the perfect sort to worm their way into Sherlock's heart like an apple and stay snugly there, becoming a bloody _exception._

Sherlock's eyes pop open. He has it all worked out, Mary's problem, and it's time to be off to go about proving it and fixing it. The majority of his mind has gone through it, and he was simply entertaining the more A.D.D. portion of it with wild musings about exceptions. "Come along then, John! We need to get ready to meet that fellow with Miss Morstan. I know precisely what to do."

"Good, good," John shrugs as he sets down the newspaper and stands from the sofa, stretch his arms and twisting to crack his back. One of his needs pop subtly as he finishes stretching. "Thought you would figure it out quickly. You always do with these things."

"Then let us be on our way," Sherlock remarks, and if part of him watches out of the corner of his eye as John slips on his jacket and shoes, Sherlock doesn't own up to it. Instead, he loops his scarf, slips it on, and buttons the top of his coat, the rest left open and flaring, as he and John fly out the door.

As they do, Sherlock makes a mental note, caving in to what seems to be so insistent:

Rule of Thumb (EDIT): Never get emotionally attached, particularly to a case or its client(s), and _never _make exceptions, _unless_ the case at hand happens to compliment you when you tell him his entire life story, looks good smothered in jam, Is a hedgehog, and looks cute in jumpers.


	2. Sherlock is an Exception

**A/N: Thanks to _dreamschemer _and their review, along with another quote from the book I realized I could use, I have decided to turn this into a twoshot. ;D**

**The last one was mainly in Sherlock's POV (albeit from a third-person standpoint), and so, this one will be primarily from John's (but again, in a third-person manner). **

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><p>They had just wrapped up the case surrounding Mary Morstan, and John had confessed his love to her and proposed, and after hearing The Strange Story of Jonathan Small to finish the case once and for all, this is what transpired:<p>

"_Well, and there is the end of our little drama," I remarked, after we had sat some time smoking in silence. "I fear that it may be the last investigation in which I shall have the chance of studying your methods. Miss Morstan has done me the honour to accept me as a husband in prospective."_

_He gave a dismal groan._

"_I feared as much," said he. "I really cannot congratulate you."_

_I was a little hurt._

"_Have you any reason to be dissatisfied with my choice?" I asked._

"_Not at all. I think she is one of the most charming young ladies I have ever met and might have been most useful in such work as we have been doing. She had a decided genius that way; witness the way which she presented that Agra plan from all the other papers of her father. But love is an emotional thing, and whatever is emotional is opposed to that true cold reason which I place above all things. I should never marry myself, lest I bias my judgment."_

The Sign of Four (second before final page in my copy); Sir Arthur Conan Doyle.

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><p>John smiles and claps his hands together once they return to the flat after finishing up their case. "Ridiculous, that one! It was like a wild goose chase for a while, but we finally got our man. So much drama," and he laughs a little, shaking his head. But he feels lighter than air, because through all of this, he fell in love, and he means to propose soon, when the timing is better. "What do you think, Sherlock?"<p>

"Yes, very dramatic," Sherlock agrees demurely. He moves for his violin in an attempt to resist having a smoke, because he could go for one right now. He saw it coming from a mile away, but he doesn't like the smell of it. He knows what John is leading up to saying about the case, and it's not going to be a good thing.

"So, uh, Sherlock. I think this might be the last case I can be on with you. I'm thinking of getting a steady job at Bart's, and I…" he chuckles giddily. "Well, I want to propose to Mary!"

Sherlock lets out the groan he knew he wouldn't be able to help make as soon as the words came from John's mouth. "I feared you'd want to do something as rushed and stupid as that. So if you're looking for some congratulations, I'm not giving it to you." And with a huff, he turns to face the window while he strings a long, slightly wavering, sad note.

"What!" John sputters, moving closer to Sherlock, a frown firmly in place. "And why the hell not? Do you have any reason why I shouldn't marry her?"

Sherlock sighs through his nose and sets down his bow. Half-turning toward John as he speaks, he prattles out swiftly, "No, none at all, and that's just the problem, John. She's wonderful – relatively clever, at least more than most women, and, yes, now that I've looked for it, I can see the attraction she may hold to men besides myself – but that doesn't change the fact that I don't see it. I don't understand love or why there's a rush for you to be off and married, and it's quite inconvenient to me, to be honest, that you're going to leave me alone on my cases from now on."

And then he turns and sharply raises his bow again, this time playing a few slow, remorseful notes. And John finds this odd, because not only did Sherlock spew nonsense that John can _feel _is a cover for something else, but he shouldn't be playing such bitter notes. They just solved a case, caught a sneaky thief, for rid of a dangerous, poison-dart shooting murderer; normally, Sherlock would be playing upbeat notes after more or less a success.

Frowning again, John moves away and heads for the kitchen, aiming to make some tea to relax with. He could also do with some sleep, but that can come later.

Sherlock said earlier in this case that exceptions disprove the rules in science. But John disagrees. As he puts water in the kettle and sets it on the stove to boil, he thinks that, no, exceptions are unique and key for research, because they are the most intriguing part of it. Without exceptions, what great scientific discoveries wouldn't have been made? Because it's exactly these exceptions that cause people to dig further into something, asking, 'Why is this an exception? What makes this special?'

Sherlock is the sort who tosses out anomalies for more accurate representation of the facts, because to him, statistics matter as results more than some of the actual results, depending on what matter he's looking into. And, it seems, regarding love and romance and marriage, he tosses out just about all of it because it doesn't follow pattern enough for him.

John thinks there is plenty pattern in love. You meet someone, you find them physically appealing, you talk to them, get to know them, experience something with them, and in no time, you're swapping numbers and dating and thinking about how compatible you may or may not be with them, and if you're compatible enough, you look for a way to spend the rest of your life with them. It seems straightforward enough, so why does it bother Sherlock so much?

Could be his sociopathic nature, though, John realizes with a sigh as the kettle whistles. He gets down his favorite mug and a packet of Earl Gray. There's something about human contact and emotion that eludes Sherlock, and it can be a bit worrisome, because John isn't always there to help Sherlock notice his mistakes or make him understand.

"Sherlock, which tea would you like?" he calls out, but he's answered only by the high, heartbreaking whines of the violin. "Fine, then. No tea for you," he hollers defiantly. Honestly, the moods Sherlock gets into…

There's a sudden screech of the violin as John walks into the living room again. He jerks, halting in his steps, and his tea sloshes onto his hand, burning him.

"Shit!" John hisses under his breath, quickly switching hands and waving the burnt one. It's going to hurt to write for a while, seeing as how the scalding tea got between his thumb and forefinger on his dominant hand. He sighs jaggedly and sits down in his armchair. He looks up at Sherlock. "What has gotten _into_ you?"

"Nothing major, John," Sherlock replies curtly. He still refuses to face John. He isn't resuming his violin playing, either. He sighs. "Sometimes I wonder."

John waits for Sherlock to say more, but when he doesn't elaborate, John sighs. "Well. I'm going to go ring shopping tomorrow. I'd like a second opinion –"

"Take Molly. She would be more than ecstatic to aid you in that department. I, however, would be useless in taste, and might only make remarks on whether or not a stone is genuine, flawed, or if the ring is secretly cheap. So Molly it is, especially since this concerns another woman; you'll need a woman's advice for it. Now then, if you please, I would like some silence. It's been a tiring week," Sherlock answers, and while he does glance at John once after he finishes speaking, John can't read Sherlock's face in the slightest.

Bewildered, John nods slowly and takes his tea into his hands. "Right… well, thanks for that, then. I'll call Molly."

He finishes drinking his tea in the quiet only filled by the occasional pluck or strum at the violin. Sherlock seems to be elsewhere, and John decides to leave him to his thoughts. Finally, with a sigh, John stands from his chair, puts away his mug, and heads for his room.

When it comes to people, Sherlock himself is an exception. Out of every person John has ever come into contact with, Sherlock is the most unique. He defies all the "rules" of normal society, it seems, because Sherlock hardly eats, hardly sleeps, thinks more than outside the box, refuses routine, gets bored easily when things aren't mentally stimulating enough, and had the strangest – and yet most effective – methods of gathering information in all categories (science, interviews, etc).

It's almost hypocritical, then, for Sherlock to dislike exceptions so much. He _is _one. And alright, maybe exceptions like the ones he spoke of – falling in love and all that – aren't his taste, but an exception is an exception.

And sometimes, quietly to himself, John wonders if Sherlock isn't also an exception for John. Mary is, he knows that, but Sherlock might be, too. Because despite what John said about never being on a case again, he knows that it feels like a lie, because if Sherlock came to him and expressed that he needed or simply wanted John to join him for an investigation, John doesn't think he would decline. In fact, he's pretty sure he would accept straight away, because Mary or no Mary, Sherlock is something unique to John, someone on the borderline of being something other than merely a "best friend."


End file.
